A new study suggests most stroke victims in the U.S. do not get adequate treatment.

About four out of five U.S. citizens reside within an hour's drive of a hospital that is equipped to treat acute strokes, but few receive the recommended treatment, an American Heart Association news release reported.

Researchers looked at the 370,000 Medicare stroke claims filed in 2011 and found only four percent were treated with tPA ("a drug that can reduce disability if given intravenously within three to four hours after the first stroke symptoms"), the news release reported.

Out of those patients 0.5 percent were given endovascular therapy, which is used to open up clogged arteries.

These therapies are believed to be available at "designated stroke centers," where the staff should be trained to diagnose and treat strokes appropriately,

"If a patient suspects they are having a stroke, they need to call 9-1-1 immediately and get to the nearest stroke center as soon as possible, which might mean bypassing another hospital that isn't set up to deliver the necessary therapy," Opeolu Adeoye, M.D., M.S., the study's lead author and associate professor of emergency medicine and neurosurgery at the University of Cincinnati, said in the news release. "We strongly suggest that patients go to the hospital by ambulance, that they or whoever is with them ask to go to a stroke center and ask for tPA."

Out of the patients studied 81 percent had access to a hospital equipped to administer tPA. Sixty-six had access to a primary stroke center and 56 percent had access to hospitals capable of providing endovascular therapy.

The researchers found 60 percent of U.S. hospitals did not administer tPA to stroke victims and discharged one in five patients who had suffered a stroke.

"Every 15-minute delay in getting treatment increases the odds of that patient not being able to go home," Adeoye said. "Calling 9-1-1 is best if a stroke is suspected because paramedics should know which hospitals are stroke centers and can alert the stroke team in advance of the patient's arrival, all of which saves time."